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arXiv · hep-ph/9610328

The role of chiral loops in $η\toπ^0π^0γγ$

S. Bellucci·G. Isidori
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Abstract

We consider the rare decay $η\toπ^0π^0γγ$ and calculate the non-resonant contribution to the amplitude to one loop in Chiral Perturbation Theory. We display our result as both a diphoton energy spectrum and a partial decay rate as a function of the photon energy cut. It turns out that the one-loop correction can be numerically very important and could be detected, at sufficiently large center-of-mass photon energies, from a measurement of the partial decay width.

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S. Bellucci, G. Isidori. 1997-06-04. The role of chiral loops in $η\toπ^0π^0γγ$. https://doi.org/10.1016/s0370-2693(97)00669-2

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